How to use the command 'valac' (with examples)

Valac is a code compiler for the Vala programming language. It is used to compile Vala source code files into executable binaries. This article will provide examples of various use cases of the ‘valac’ command.

Use case 1: Compile a vala file with gtk+

Code:

valac path/to/file.vala --pkg gtk+-3.0

Motivation: Compiling a Vala file with gtk+ is necessary when working with graphical user interfaces in Vala. Gtk+ is a popular toolkit for creating graphical applications, and by using the --pkg gtk+-3.0 argument, the valac compiler is able to include the necessary gtk+ libraries during the compilation process.

Explanation:

• valac: The command to invoke the Vala compiler.
• path/to/file.vala: The path to the Vala source code file that needs to be compiled.
• --pkg gtk+-3.0: Specifies that the gtk+ library with version 3.0 needs to be used during the compilation process.

Example output:

Compilation successful. The valac command will generate an executable binary based on the provided Vala source code file, using the specified gtk+ library.

Use case 2: Display version info

Code:

valac --version

Motivation: Displaying the version info of the valac compiler can be useful when troubleshooting or when checking for compatibility with certain Vala language features.

Explanation:

• valac: The command to invoke the Vala compiler.
• --version: This argument tells the valac compiler to display its current version information.

Example output:

valac 0.52.3

The example output shows the version number of the valac compiler currently installed on the system.

Use case 3: Display helper message

Code:

valac --help

Motivation: The --help argument is used to display a helper message that provides information about the available options and usage of the valac compiler.

Explanation:

• valac: The command to invoke the Vala compiler.
• --help: This argument tells the valac compiler to display its helper message.

Example output:

Usage:
  valac [OPTION?] [FILE?]+

Compiler Options:
  ...
...

The example output shows a portion of the helper message displayed by the valac compiler. It provides an overview of the available compiler options and their usage.

Conclusion:

This article provided examples of various use cases of the ‘valac’ command, demonstrating how to compile Vala source code files with gtk+, display version information, and access the helper message. The valac compiler is an essential tool for Vala developers, enabling them to compile their Vala code into executable binaries.